I use this command to create a e-mail address policy based on a group membership use the following command:
New-EmailAddressPolicy "" -RecipientFilter {((MemberOfGroup -eq "GroupPath"))} -EnabledPrimarySMTPAddressTemplate ‘ ’
PolicyName – Policy name.
GroupPath – Distinguished name of group in Active Directory.
Emailtemplate – Primary email address template e.g. SMTP:%g@corpdomain.com
Use this link for E-mail address templates: Email address policies
Example:
new-EmailAddressPolicy "Email-Policy-Name" -RecipientFilter {((MemberOfGroup -eq "CN=GroupName,OU=OU-Name,OU=Users,DC=Corp,DC=local") -and (RecipientType -eq 'UserMailbox'))} -EnabledPrimarySMTPAddressTemplate 'SMTP:%g@corpdomain.com'